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The Simplex Gas Engine.

701

•was the cause of failure.* In the Simplex engine a constant
•srrower of sparks takes place in the chamber x, the current
passing through the insulator u and back by v. In the figure the
cylinder is being charged from s, through Q, but when the slide
moves to the right, R connects w with x, and ignition occurs
•with certainty. (See App. /,/. 773, and App. IV., p. 963.)

We may now describe the SIMPLEX ENGINE (Systeme Delamare-
Deboutteville et Malandin), Figs. 683 to 688, as a type of a
•well-designed gas engine. A is the cylinder, supported on the
•bed plate H, and surrounded by a water jacket B, which also
protects the slide casing and exhaust outlet; N is the mixing
•chamber, and c the piston or plunger. D is the connecting rod,
E the crank, F the balance weights, R the crank shaft, and G G the
'fly wheels, having a pulley p attached for driving purposes. Pipe j
:is always open to air, and the gaspipe K admits gas when cock L
is opened. But such gas is only allowed to enter the cylinder
.at proper times, viz., when the charging valve M is opened by
projection h on the slide spindle g. As the cycle occupies two
revolutions, the shaft Q (which moves the slide d backward and
forward through the disc crank/) makes two rotations to one on
the main shaft, and the wheels at R and s together have a velocity
Tatio of 2:1. The charging and ignition having been described
*the governing and exhaust arrangements remain. Taking the
former, shewn in Figs. 687 and 688, the method adopted, as in
-other gas engines, is to cut out one or more chargings when the
•engine speed increases. Upon the spindle h is a small tapered
6 rocker '/, &&& when this is allowed to catch the stem k of the
•charging valve the latter is opened The governor is a pendulum
n /, whose lower end is lifted to the right by the rocker /, and,
being allowed to return freely, its time of fall is invariable.
Noting that the rocker/ is constantly depressed, as in Fig. 688,
•by a spring, suppose engine speed to be normal, and / to be
•moved to the right, lifting the pendulum. Returning, the pen-
dulum bears slightly upon the rocker, catch m lifts/ to the hori-
zontal, and the valve is opened. But if the slide travel too
quickly, m misses/when returning, and the result is a 'misfire,'

* M. Deboutteville. iodines to the former, Prof. Wm. Robinson to the
latter (muse.